

At
the lower end of the spar there is a cut-out (above, centre) to allow
the sail to be fed into the luff groove, and at each end a sort of cap
fits over the end of the spar (above, right). The sail is attached at
the head and the tack by a small ring welded to each of these end caps.
This is illustrated in the photo (left), which shows the top of the
spar, the end cap (with black rope attaching the sail to the ring) and
the top swivel (described below).
A robust clevis pin passes through
the end cap, forestay terminal and top swivel. The photo (right) shows
all three components, separated for clarity, with the red line showing
where the clevis pin fits.

The
supplied length of the spar (over 4500mm) is more than adequate for a
Wayfarer genoa, but there is still plenty of room between the genoa
halyard mast sheave and the top of the spar (see photo, right). This is
the gap that would be spanned by a safety wire, if fitted.
Incidentally,
the aluminium profile only comes in lengths up to 2m, so obviously the
spar has to be supplied in several lengths. They are pre-cut to the
exact total length required to match the supplied forestay, and cannot
be shortened without replacing the forestay.